File folders of the type contemplated herein are generally formed of two stiff panels interconnected by a flexible tape which is folded to form a gusset to provide an expansion-type hinge. These file folders have, for the most part, been hand manufactured for many years. The panels are placed on a flat surface with the edges spaced apart a fixed distance. The flexible tape is generally applied by hand to the edges of the panels. The gusset is formed by manually pressing the tape on a creasing plate to fold the tape between the panels. After the tape has been creased, the file folder is folded and stacked.